Arthroderma tuberculatum and Arthroderma multifidum Isolated from Soils in Rook (Corvus frugilegus) Colonies as Producers of Keratinolytic Enzymes and Mineral Forms of N and S

Abstract

Keratinolytic fungi representing the genus Arthroderma that were isolated from the soils of a rook (Corvus frugilegus) colony were used as biological agents for the disposal of waste feathers. The aim of this study was to assess the abilities of Arthroderma tuberculatum and Arthroderma multifidum fungi with a varied inflow of keratin matter to biodegrade waste feathers. The evaluation was based on the determination of feather mass loss, the activity of keratinolytic enzymes, and the content of mineral N and S forms. It was found that the activity of protease released by the fungi contributed to an increase in the level of soluble proteins and peptides and the concentration of ammonium ions, as well as alkalization of the culture medium. Keratinase activity was significantly correlated with sulfate release, especially in A. tuberculatum cultures. The strains of A. tuberculatum fungi isolated from the soil with the highest supply of organic matter, i.e., strains III, IV, and V, had the lowest enzymatic activity, compared to the A. multifidum strains, but they released mineral nitrogen and sulfur forms that are highly important for fertilization, as well as nutritionally important peptides and amino acids. A. tuberculatum strains can be used for the management of waste feathers that can be applied in agricultural practice.

Optimization of Conditions for Feather Waste Biodegradation by Geophilic Trichophyton ajelloi Fungal Strains towards Further Agricultural Use

“…Bohacz [ 12 ] identified the latter as the most reliable indicator of the biodegradation process of chicken feathers and described it as an ‘economic coefficient’. The process of S-keratin mineralization was also pointed out by Bohacz, et al [ 14 ] as another important aspect of chicken feather biodegradation. The latter authors pointed out that in addition to nitrogen mineralization, organic sulfur mineralization was the determinant of fungal keratinolysis efficiency.…”

“…Amino acid composition, i.e., concentration of aspartate (Asp), threonine (Thr), serine (Ser), glutamate (Glu), proline (Pro), glycine (Gly), alanine (Ala), cysteine (Cys), valine (Val), methionine (Met), isoleucine (Ile), leucine (Leu), tyrosine (Tyr), phenylalanine (Phe), histidine (His), lysine (Lys), arginine (Arg), and tryptophan (Trp) of the optimized cultures tested were carried out according to the methodology described in detail by Bohacz, et al [ 14 ]. For this purpose, culture fluids of the fungus strain III from 18-day optimized stationary cultures, with the addition of xylose and glucose, incubated at 20 and 37 °C, and from an agitated culture were selected.…”

“…These are wastes which pose low risk to human and animal health that can be reused for various purposes. Environmentally friendly technologies dominate among the proposals regarding the possibility of managing this waste, i.e., composting with lignocellulosic waste [ 6 , 7 , 8 , 9 , 10 , 11 ], microbial processing to obtain bioproducts with high fertilizer and feed potential [ 12 , 13 , 14 ], and obtaining keratinolytic enzymes for medical, pharmaceutical, industrial and bioenergy applications [ 15 ]. Implementing biological methods of keratin waste management is an alternative option to existing physical and chemical methods [ 1 ], which have an adverse impact on the environment and generate additional costs from an economic perspective.…”

“…Native keratins are hard-to-degrade proteins, available as a nutritional substrate only to a small number of microorganisms. Among the keratinolytic microorganisms capable of utilizing native keratin as the sole source of C and energy, bacteria of the genera Bacillus , Sarcina , Streptomyces , and fungi from the group of dermatophytes and Chrysosporium can be mentioned [ 12 , 13 , 14 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. In the group of dermatophytes, in addition to pathogenic species, there are saprotrophic species called geophilic dermatophytes, which do not show affinity to higher organisms [ 23 , 24 ].…”

“…In the group of dermatophytes, in addition to pathogenic species, there are saprotrophic species called geophilic dermatophytes, which do not show affinity to higher organisms [ 23 , 24 ]. Saprotrophic keratinomycetes, in addition to cultivated soils [ 25 , 26 ], soils with a constant supply of keratinous matter [ 14 , 24 ], and composts [ 10 ], colonize feathers and nests of birds or mammalian hair [ 27 ], as well as bottom sediments, sewage, and municipal waste [ 21 , 28 ]. In cultivated soils and keratin-based composts, keratinolytic fungi are considered natural biofertilizers, as they release mineral forms of nitrogen and sulfur during the enzymatic biodegradation of native keratin (feathers, hair, other animal remains), which are assimilable by plants [ 10 , 12 ].…”